1. Field of the Invention
The present invention relates generally to a method and apparatus for transmitting and receiving rich media content, and more particularly to a method and apparatus for transmitting and receiving objects of a rich media application.
2. Description of the Related Art
A rich media application is an application that includes multimedia content such as audio, video and text, interactive information exchange and control between a server and a client, interactive information exchange and control with users, temporal and spatial arrangements between these elements. Most noticeably, the rich media is generally distinguishable from the multimedia in terms of interactivity. That is, rich media is created in a structure that is described with information such as data indicating a temporal/spatial relationship, an event for expressing interactivity, and operation data, in addition to media data, graphic element data, and attribute data of respective element values, and these are each expressed in languages provided by a specific rich media engine. The languages, which can be applied in various ways, include, for example, MPEG4 Lightweight Application of Scene Representation (LASeR), MPEG4 Binary Format for Scene (BIFS), Scalable Vector Graphics (SVG) of World Wide Web Consortium (W3C), etc.
In order to drive the application, an operation of converting the above information pieces to a hierarchical structure is needed. The above operation is for layering or stratifying rich media elements from a root element (highest node) to a child element (lowest node) of the root in temporal/spatial order of driven elements. The hierarchical (or layered) structure is formed in a tree structure. One root may have a plurality of child nodes, and each node is composed of elements constituting the node, types of attributes representing each element, and respective attribute values. A rich media engine driving the application realizes each element in the hierarchical structure using its associated attribute type and attribute value. Herein, the attribute type will be referred to as “attribute.”
The conventional rich media application provides a rich media service using hierarchical structure information of a content object created during the content object's creation. That is, the rich media application realizes completed-hierarchical structure information pieces of the created rich media information pieces, as they are, because it cannot realize a rich media service if at least one of node information pieces, i.e. element, attribute and attribute value, of a hierarchical structure, for realizing the rich media service is undefined. For this reason, the conventional driver should drive only the application created by a creator.